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1.
Cell Tissue Res ; 384(3): 745-756, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33660050

RESUMO

Skeletal muscle fibers are classified as slow-twitch and fast-twitch fibers, which have different reactive oxygen species (ROS) metabolism and mitochondrial biogenesis. Recently, Attractin (Atrn), which encodes secreted (sAtrn) and transmembrane (mAtrn)-type proteins, has been shown to be involved in free radical scavenging. Although Atrn has been found in skeletal muscle, little is known about the expression levels and function of Atrn in each muscle fiber type. Therefore, we investigate sAtrn and mAtrn expression levels in the slow-twitch soleus (sol) and fast-twitch extensor digitorum longus (EDL) muscles as well as the morphology and expression levels of antioxidant enzymes and functional mitochondrial markers using Atrn-deficient muscles. Both types of Atrn were expressed in the sol and EDL. mAtrn was mainly expressed in the adult sol, whereas sAtrn expression levels did not differ between muscle types. Moreover, mAtrn in the sol was abundantly localized in the subsarcolemmal area, especially in the myoplasm near mitochondria. Atrn-deficient Zitter rats showed muscle fiber atrophy, myofibril misalignment, mitochondrial swelling and vacuolation in the sol but not EDL. Furthermore, the Atrn-deficient sol exhibited a marked reduction in antioxidant enzyme SOD1, GPx1, catalase and Prx6 and mitochondrial functional protein, UCP2, expression. Even Atrn-deficient EDL showed a significant reduction in Prx3, Prx6, UCP2 and UCP3 expression. These data indicate that Atrn-deficiency disturbs ROS metabolism in skeletal muscles. In particular, mAtrn is involved in metabolism in the slow-twitch sol muscle and mAtrn-deficiency may cause ROS imbalance, resulting in morphological abnormalities in the muscle.


Assuntos
Proteínas de Membrana/deficiência , Fibras Musculares de Contração Lenta , Doenças Musculares/metabolismo , Animais , Masculino , Fibras Musculares de Contração Lenta/metabolismo , Fibras Musculares de Contração Lenta/patologia , Ratos , Ratos Sprague-Dawley
2.
Neurochem Res ; 46(4): 853-865, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33439431

RESUMO

The A11 region plays a role in numerous physiological functions, including pain and locomotor activity, and consists of a variety of neurons including GABAergic, calbindin positive (Calb+), and dopaminergic (DA) neurons. However, the neurochemical nature of Calb+ neurons and their regulatory role in the A11 region remain largely unknown. In this study, we examined the kind of functional markers co-expressed in the Calb+ neurons using sections from 8-week-old rats. To examine a marker related to classical neurotransmitters, we performed in situ hybridization for vesicular glutamate transporter 2 (vGluT2) or glutamate decarboxylase (GAD) 65 and 67, in conjunction with Calb immunohistochemistry. We found cellular co-expression of Calb with vGluT2 or GAD65/67 throughout the A11 region. Nearly all Calb+/GAD65/67+ neurons were found in the rostral-middle aspect of the A11 region. In contrast, Calb+/vGluT2+ neurons were found predominantly in the middle-caudal aspect of the A11 region. For receptors and neuropeptides, we performed immunohistochemistry for androgen receptor (AR), estrogen receptors (ERα and ERß), and calcitonin gene-related peptide (CGRP). We found that Calb+ neurons co-expressed AR in the rostral aspect of the A11 region in both male and female rats. However, we rarely find cellular co-expression of Calb with ERα or ERß in this region. For CGRP, we found both Calb+ neurons with or without CGRP expression. These results demonstrate that Calb+ neurons co-express many functional markers. Calb+ neurons have a distinct distribution pattern and may play a variety of regulatory roles, depending on their location within the A11 region.


Assuntos
Encéfalo/metabolismo , Calbindinas/metabolismo , Neurônios/metabolismo , Animais , Encéfalo/citologia , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Receptor alfa de Estrogênio/metabolismo , Receptor beta de Estrogênio/metabolismo , Feminino , Glutamato Descarboxilase/metabolismo , Masculino , Ratos Sprague-Dawley , Receptores Androgênicos/metabolismo , Proteína Vesicular 2 de Transporte de Glutamato/metabolismo
3.
Nitric Oxide ; 78: 41-50, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29792933

RESUMO

Neuronal nitric oxide synthase (nNOS) is involved in nigrostriatal dopaminergic (DA) neurodegeneration. However, little is known about the distribution patterns and functions of nNOS in slowly progressive DA neurodegeneration. Here we describe the spatiotemporal change in nNOS expression over the course of neurodegeneration and the effect of short- or long-term treatment with the nNOS inhibitor, 7-nitroindazole (7-NI), in zitter (zi/zi) rats. In the substantia nigra pars compacta (SNc), nNOS expression was significantly increased with progression of neurodegeneration. nNOS-immunoreactive (ir) cells were in the vicinity of tyrosine hydroxylase-ir (TH-ir) DA neurons, and some of these cells were also positive for calbindin. nNOS in the caudate-putamen (CPu) showed little difference during progression of neurodegeneration. However, immunoelectron microscopic analysis revealed that abundant TH-ir fibers in the CPu were degenerated due to compression by vacuoles that contained swollen neuronal and glial elements. Additionally, lipid peroxidation as a marker of membrane oxidation was significantly increased in zi/zi rats. Short-term 7-NI treatment attenuated the increase in lipid peroxidation and inhibited the vacuolation in the CPu. Moreover, long-term 7-NI treatment significantly protected TH-ir neurons in the SNc, and TH-ir fibers and DA contents in the CPu. These results show that nNOS exacerbates slowly progressive DA neurodegeneration, and the neuroprotective effects of 7-NI may result from suppression of membrane oxidation that causes abnormal membrane structures in zi/zi rats.


Assuntos
Neurônios Dopaminérgicos/patologia , Neurônios Dopaminérgicos/fisiologia , Degeneração Neural/fisiopatologia , Óxido Nítrico Sintase Tipo I/metabolismo , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Animais , Sequência de Bases , Núcleo Caudado/efeitos dos fármacos , Núcleo Caudado/metabolismo , Núcleo Caudado/patologia , Dopamina/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Indazóis/farmacologia , Peroxidação de Lipídeos/fisiologia , Masculino , Proteínas de Membrana/genética , Degeneração Neural/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Óxido Nítrico Sintase Tipo I/genética , Parte Compacta da Substância Negra/efeitos dos fármacos , Parte Compacta da Substância Negra/metabolismo , Parte Compacta da Substância Negra/patologia , Putamen/efeitos dos fármacos , Putamen/metabolismo , Putamen/patologia , RNA Mensageiro/metabolismo , Ratos , Deleção de Sequência , Vacúolos/metabolismo
4.
Neurochem Res ; 42(8): 2142-2153, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28303496

RESUMO

The A11 dopaminergic cell group is the only group among the A8-A16 dopaminergic cell groups that includes neurons innervating the spinal cord, and a decrease in dopaminergic transmission at the spinal cord is thought to contribute to the pathogenesis of restless legs syndrome. However, the mechanisms regulating the neuronal activity of A11 dopaminergic neurons remain to be elucidated. Unraveling the neuronal composition, distribution and connectivity of A11 neurons would provide insights into the mechanisms regulating the spinal dopaminergic system. To address this, we performed immunohistochemistry for calcium-binding proteins such as calbindin (Calb) and parvalbumin (PV), in combination with the retrograde tracer Fluorogold (FG) injected into the spinal cord. Immunohistochemistry for Calb, PV, or tyrosine hydroxylase (TH), a marker for dopaminergic neurons, revealed that there were at least three types of neurons in the A11 region: neurons expressing Calb, TH, or both TH and Calb, whereas there were no PV-immunoreactive (IR) cell bodies. Both Calb- and PV-IR processes were found throughout the entire A11 region, extending in varied directions depending on the level relative to bregma. We found retrogradely labeled FG-positive neurons expressing TH, Calb, or both TH and Calb, as well as FG-positive neurons lacking both TH and Calb. These findings indicate that the A11 region is composed of a variety of neurons that are distinct in their neurochemical properties, and suggest that the diencephalospinal dopamine system may be regulated at the A11region by both Calb-IR and PV-IR processes, and at the terminal region of the spinal cord by Calb-IR processes derived from the A11 region.


Assuntos
Neurônios Dopaminérgicos/fisiologia , Medula Espinal/citologia , Medula Espinal/fisiologia , Animais , Calbindinas/análise , Neurônios Dopaminérgicos/química , Masculino , Vias Neurais/química , Vias Neurais/citologia , Vias Neurais/fisiologia , Parvalbuminas/análise , Ratos , Ratos Sprague-Dawley , Medula Espinal/química , Tirosina 3-Mono-Oxigenase/análise
5.
J Neurochem ; 135(6): 1232-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26442961

RESUMO

The nucleus accumbens (Nac) mediates the reinforcing and motor stimulating properties of psychostimulants. It receives dopaminergic afferents from the ventral midbrain and is divided into two distinct subregions: shell and core. Each of these contains two subtypes of medium spiny neurons, which express either dopamine D1 (D1R) or D2 (D2R) receptors. However, functional dissociation between the two subtypes in psychostimulant response remains to be elucidated. We performed selective ablation of each subtype in the Nac shell in mice, using immunotoxin-mediated cell targeting, and examined the behavioral sensitization evoked by repeated administration of methamphetamine. The D1R cell-ablated mice exhibited delayed induction of sensitized locomotion compared to control mice, whereas the D2R cell-ablated mice showed a mildly enhanced rate of induction of sensitization. In vivo microdialysis revealed a marked blockade of the increase in extracellular dopamine in the Nac of the D1R cell-ablated animals in response to methamphetamine, indicating that the observed delay in behavioral sensitization in these mice involves an impairment in accumbal dopamine release. Our results reveal differential roles of D1R- and D2R-containing accumbal shell neurons in the development of behavioral sensitization to psychostimulants. Behavioral sensitization, enhanced motility by repetitive psychostimulant administration, is a model of drug addiction. Here, we show that the nucleus accumbens (Nac) shell neurons containing dopamine D1 receptor (D1R) or D2 receptor (D2R) play distinct roles in behavioral sensitization triggered by methamphetamine, and that D1R-containing neurons enhance the induction of behavioral sensitization at the early phase, whereas D2R-containing neurons act to suppress the rate of development of the behavior.


Assuntos
Comportamento Animal , Estimulantes do Sistema Nervoso Central/farmacologia , Neurônios/metabolismo , Núcleo Accumbens/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Dopamina/metabolismo , Metanfetamina/farmacologia , Camundongos , Núcleo Accumbens/efeitos dos fármacos
6.
Pathophysiology ; 21(4): 309-16, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25270870

RESUMO

INTRODUCTION: The literature described that neural damage caused by ischemia definitely occurs in brain areas. However, few studies have shown real-time changes of extracellular monoamine levels at the time of transient ischemia. METHODS: We examined changes in the responses of dopamine (DA) and serotonin (5-HT) release in the nucleus accumbens (ACC) of rats treated with four-vessel occlusion (4VO) in experiment 1. In the second experiment, we investigated the selective neural vulnerabilities among the ACC, lateral hypothalamus (LH), and frontal cortex (FC) of rats treated with 4VO and four days of reperfusion. RESULTS: The extracellular levels of DA and 5-HT were remarkably increased 200- and 20-fold upon the 10-min clipping of both common carotid arteries in transient cerebral ischemia, respectively. Each increased monoamine release returned to the baseline levels immediately. The release of DA in the ACC and FC was significantly decreased in the rats treated with the coagulation of bilateral vertebral arteries (2VO), compared with that of sham-operated rats. K(+)-induced DA release in the ACC and FC of 4VO-treated rats was increased without alteration of DA content. DISCUSSION: Surviving dopaminergic neurons in the ACC and FC showed neural hyperfunction associated with the monoamine release, serotonergic neurons in particular these areas exhibiting functional resistance to the transient ischemic change. CONCLUSION: It is suggested that the remarkable extracellular release of DA and 5-HT was not the cause of the ischemic delayed neural degeneration in each brain area, and that the functions of neurotransmitter release involved remarkable resistance to the transient ischemia.

7.
Med Mol Morphol ; 47(4): 207-12, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24326379

RESUMO

The clinical course of patients with chronic hepatitis B (CH-B) was greatly changed by the introduction of nucleoside analogues. We often encounter patients where the serum level of albumin recovers quickly following the treatment. In this study, we focused carefully on the changes in serum albumin level noted during nucleoside analogue therapy, in an effort to clarify the mechanism behind the restoration of albumin production. We observed changes in serum albumin levels during nucleoside analogue therapy in 12 patients with CH-B and studied the mechanism behind the restoration of albumin production following the therapy. The serum level of albumin was significantly increased very soon after the treatment was started. Prior to treatment with nucleoside analogues, the albumin signal for mRNA was only slightly seen in the peri-portal area, whereas 12 months after the treatment, the liver tissue presented an obvious signal of albumin mRNA. Serum levels of hepatocyte growth factor (HGF) were significantly decreased 12 months after the treatment. In this study, we demonstrated that nucleoside analogues decrease HGF through the suppression of hepatocyte damage, leading to the restoration of albumin production in patients with CH-B.


Assuntos
Antivirais/uso terapêutico , Guanina/análogos & derivados , Hepatite B Crônica/sangue , Lamivudina/uso terapêutico , Albumina Sérica/metabolismo , Adulto , Idoso , Antivirais/farmacologia , Feminino , Expressão Gênica , Guanina/farmacologia , Guanina/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Fator de Crescimento de Hepatócito/sangue , Humanos , Lamivudina/farmacologia , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Albumina Sérica/genética , Fator de Crescimento Transformador beta1/sangue , Adulto Jovem
8.
BMC Res Notes ; 17(1): 61, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38433213

RESUMO

OBJECTIVE: The neural correlates of creativity are not well understood. Using an improvised guitar task, we investigated the role of Broca's area during spontaneous creativity, regardless of individual skills, experience, or subjective feelings. RESULTS: Twenty guitarists performed improvised and formulaic blues rock sequences while hemodynamic responses were recorded using functional near-infrared spectroscopy. We identified a new significant response in Broca's area (Brodmann area [BA] 45L) and its right hemisphere homologue during improvised playing but not during formulaic playing. Our results indicate that bilateral BA45 activity is common during creative processes that involve improvisation across all participants, regardless of subjective feelings, skill, age, difficulty, history, or amount of practice. While our previous results demonstrated that the modulation of the neural network according to the subjectively experienced level of creativity relied on the degree of deactivation in BA46L, our current results independently show a common concurrent activity in BA45 in all participants. We suggest that this is related to the sustained execution of improvisation in "motor control," analogous to motor planning in speech control.


Assuntos
Área de Broca , Música , Humanos , Emoções , Redes Neurais de Computação
9.
J Gastroenterol Hepatol ; 27(6): 1044-50, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22433056

RESUMO

BACKGROUND AND AIM: Percutaneous radiofrequency ablation (RFA) has been shown to be a highly effective treatment for hepatocellular carcinoma (HCC). We investigated the controllability of HCC and explored the algorithm of therapeutic strategy for HCC in patients who met the RFA criteria. METHODS: We enrolled 472 patients with HCC who met the RFA criteria (≤ 3 nodules, ≤ 3 cm) and underwent RFA for initial therapy. Patients who underwent repeated RFA were evaluated retrospectively when HCC exceeded the RFA criteria, or the functional hepatic reserve progressed to Child-Pugh grade C. RESULTS: Overall survival rates were: 1 year, 96%; 3 years, 79%; and 5 years, 56%. In 5 years, 14% of patients progressed to Child-Pugh grade C. Meanwhile, 47% of patients exceeded the RFA criteria. Annually, 8% of patients deviated from the RFA criteria. The percentage of patients who were able to receive RFA significantly decreased at the fourth session compared with up to the third session. The survival rates decreased at the rate of 7% annually until the third year after the initial RFA. Afterwards, it shifted to a decrease at the rate of 12% annually. In a multivariate analysis, the presence of hepatitis C virus infection and the existence of a single tumor were identified as significant independent factors contributing to probabilities exceeding the RFA criteria. CONCLUSIONS: HCC was controlled by RFA up to three RFA treatments and 3 years from the initial therapy. On this basis, we propose a "three (times) × 3 (years) index" for considering a shift from RFA to other treatment modalities.


Assuntos
Carcinoma Hepatocelular/cirurgia , Ablação por Cateter/métodos , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Carcinoma Hepatocelular/patologia , Progressão da Doença , Feminino , Humanos , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
10.
Hepatogastroenterology ; 59(119): 2264-8, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22389294

RESUMO

BACKGROUND/AIMS: We have evaluated the effectiveness of systemic chemotherapy for patients with extrahepatic metastasis from hepatocellular carcinoma. METHODOLOGY: We examined the background, survival rates, median survival time and side effects of 15 cases in which systemic chemotherapy using carboplatin and 5-fluorouracil was done (chemotherapy group) and 59 cases in which chemotherapy was not done (non-chemotherapy group) out of a total of 74 cases of patients with extrahepatic metastasis from hepatocellular carcinoma. RESULTS: The prognoses of the 15 chemotherapy cases and the 59 non-chemotherapy cases were as follows: 66.0%, 33.3%, 20.0% at 6 months, 12 months, 18 months respectively for the chemotherapy cases and 44.0%, 18.2%, 7.1% respectively for the non-chemotherapy cases. Median survival periods were 10.7 months for the chemotherapy group and 5.1 months for the non-chemotherapy group. A significantly better prognosis of survival (p=0.037) was identified in the chemotherapy group and no serious side effects were observed. CONCLUSIONS: The present research preceded the approval of sorafenib. This systemic combination chemotherapy will provide an extended survival prognosis and is thus considered to be comparatively safe and effective in those patients.


Assuntos
Neoplasias das Glândulas Suprarrenais/tratamento farmacológico , Neoplasias das Glândulas Suprarrenais/secundário , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/secundário , Neoplasias Hepáticas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/secundário , Neoplasias das Glândulas Suprarrenais/mortalidade , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Ósseas/mortalidade , Carboplatina/administração & dosagem , Carcinoma Hepatocelular/mortalidade , Distribuição de Qui-Quadrado , Feminino , Fluoruracila/administração & dosagem , Humanos , Estimativa de Kaplan-Meier , Modelos Logísticos , Neoplasias Pulmonares/mortalidade , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
11.
Brain Struct Funct ; 226(4): 1253-1267, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33625560

RESUMO

Serotonin (5-HT) and dopamine (DA) are involved in the regulation of social behaviors. However, the effects of their interactions on social behavior are not well understood. In this study, rats received a serotonergic neurotoxin injection into the raphe nuclei and/or systemic administration of L-3, 4-dihydroxyphenylalanine (L-DOPA), and their agonistic behaviors were investigated using the resident-intruder (RI) paradigm. Rats in the DA + /5-HT-group, which were administered both monoaminergic treatments, exhibited intense jump and flight responses to intruders. These behaviors were not observed in rats that received either 5-HT lesions or L-DOPA treatment only. To address the neural basis of these aberrant behaviors, we compared c-Fos immunoreactivity in the brain among the different groups. The DA + /5-HT-group had c-Fos activation in areas related to anti-predatory defensive behaviors, such as the ventromedial hypothalamic nucleus, premammillary nucleus, and periaqueductal gray. Moreover, this group had increased c-Fos expression in the ventroposterior part of the anterior olfactory nucleus (AOVP). To test the involvement of this area in the aberrant behaviors, cytotoxic lesions were performed in the AOVP prior to the monoaminergic treatments, and subsequent behaviors were examined using the RI test. The AOVP-lesioned DA + /5-HT-rats had attenuation of the aberrant behaviors. Together, these results suggest that the AOVP is involved in the generation of the aberrant defensive behaviors, and that 5-HT/DA balance is important in the regulation of social behaviors.


Assuntos
Comportamento Agonístico , Animais , Dopamina , Levodopa , Proteínas Proto-Oncogênicas c-fos/metabolismo , Núcleos da Rafe/metabolismo , Ratos , Serotonina
12.
Brain Res ; 1762: 147425, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33737065

RESUMO

The amygdala plays a crucial role in anxiety-related behavior and various neuropsychiatric disorders. The offspring of dams, administered methylazoxymethanol acetate (MAM) intraperitoneally at gestational day 15, exhibit micrencephaly and anxiety-related behavior, such as hyperactivity in rearing and crossing behavior, alongside a distinct Fos expression profile in the basolateral (BLA) and central amygdala. However, the histochemical underpinnings of these changes remain to be elucidated. To determine the histochemical alterations in MAM-induced model rats, we performed Nissl staining, immunohistochemistry for parvalbumin (PV) or calbindin (Calb), and immunohistochemistry for PV in conjunction with in situ hybridization for glutamate decarboxylase (GAD). We compared immunoreactivity in the BLA between normal and MAM-induced model rats and observed a significant decrease in the number of PV-positive neurons in MAM-induced model rats; however, no significant differences in the number of Nissl- and Calb-positive neurons were observed. We did not detect any significant between-group differences with regards to the effects of environmental enrichment on the number of PV-positive neurons in the BLA. Double-labeling for GAD and PV revealed that many PV-positive neurons colocalized with digoxigenin-GAD65/67 signals. In addition, GAD/PV double-positive neurons and the total number of GAD-positive neurons in the BLA were lower in the MAM-induced model rats. These results indicate that histochemical alterations observed in the BLA of the MAM-induced model rats may attribute to an aberrant GABAergic inhibitory system.


Assuntos
Complexo Nuclear Basolateral da Amígdala/metabolismo , Neurônios GABAérgicos/metabolismo , Interneurônios/metabolismo , Acetato de Metilazoximetanol/análogos & derivados , Microcefalia/metabolismo , Parvalbuminas/metabolismo , Animais , Complexo Nuclear Basolateral da Amígdala/química , Complexo Nuclear Basolateral da Amígdala/efeitos dos fármacos , Carcinógenos/toxicidade , Feminino , Neurônios GABAérgicos/química , Neurônios GABAérgicos/efeitos dos fármacos , Interneurônios/química , Interneurônios/efeitos dos fármacos , Masculino , Acetato de Metilazoximetanol/toxicidade , Microcefalia/induzido quimicamente , Microcefalia/psicologia , Parvalbuminas/análise , Gravidez , Ratos , Ratos Sprague-Dawley
13.
Brain Pathol ; 31(2): 333-345, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33220123

RESUMO

Iron accumulation in the CNS is associated with many neurological diseases via amplification of inflammation and neurodegeneration. However, experimental studies on iron overload are challenging, since rodents hardly accumulate brain iron in contrast to humans. Here, we studied LEWzizi rats, which present with elevated CNS iron loads, aiming to characterise choroid plexus, ependymal, CSF and CNS parenchymal iron loads in conjunction with altered blood iron parameters and, thus, signifying non-classical entry sites for iron into the CNS. Non-haem iron in formalin-fixed paraffin-embedded tissue was detected via DAB-enhanced Turnbull Blue stainings. CSF iron levels were determined via atomic absorption spectroscopy. Ferroportin and aquaporin-1 expression was visualised using immunohistochemistry. The analysis of red blood cell indices and serum/plasma parameters was based on automated measurements; the fragility of red blood cells was manually determined by the osmotic challenge. Compared with wild-type animals, LEWzizi rats showed strongly increased iron accumulation in choroid plexus epithelial cells as well as in ependymal cells of the ventricle lining. Concurrently, red blood cell macrocytosis, low-grade haemolysis and significant haemoglobin liberation from red blood cells were apparent in the peripheral blood of LEWzizi rats. Interestingly, elevated iron accumulation was also evident in kidney proximal tubules, which share similarities with the blood-CSF barrier. Our data underscore the importance of iron gateways into the CNS other than the classical route across microvessels in the CNS parenchyma. Our findings of pronounced choroid plexus iron overload in conjunction with peripheral iron overload and increased RBC fragility in LEWzizi rats may be seminal for future studies of human diseases, in which similar constellations are found.


Assuntos
Plexo Corióideo/química , Modelos Animais de Doenças , Epêndima/química , Sobrecarga de Ferro/patologia , Ferro/metabolismo , Animais , Hemólise , Sobrecarga de Ferro/genética , Proteínas de Membrana/genética , Mutação , Fragilidade Osmótica , Ratos
14.
Med Mol Morphol ; 43(3): 134-8, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20857261

RESUMO

To examine the mRNA expression of hepatobiliary transporters in primary biliary cirrhosis (PBC) patients and to compare bile acid absorption, synthesis, and efflux in patients with non-end-stage and end-stage PBC, we obtained liver samples from PBC patients by percutaneous needle biopsy. End-stage PBC was defined as follows: histological stage IV; cirrhosis; serum total bilirubin, ≥4.0 mg/dl; and Child-Pugh Class C. The mRNA expression levels of sodium taurocholate cotransporting polypeptide (NTCP), bile salt export pump (BSEP), and hepatic cholesterol 7α-hydroxylase (CYP7A1) were significantly higher in the PBC patients than in the controls (P < 0.01). The mRNA levels of NTCP and BSEP were significantly higher in the end-stage PBC patients than in the controls (P < 0.01). However, hepatic CYP7A1 mRNA expression decreased significantly (by 70%) in the patients with end-stage PBC as compared to the controls and the patients with non-end-stage PBC (P < 0.01). The hepatic expression of transporters mediating bile acid influx and efflux showed sustained elevation, whereas that of the rate-limiting enzyme for bile acid biosynthesis was attenuated in the end-stage PBC patients. Thus, mechanisms may be present preventing the accumulation of toxic bile acids in the hepatocytes of end-stage PBC patients.


Assuntos
Transportadores de Cassetes de Ligação de ATP/biossíntese , Colesterol 7-alfa-Hidroxilase/biossíntese , Doença Hepática Terminal/metabolismo , Cirrose Hepática Biliar/metabolismo , Fígado/metabolismo , Transportadores de Ânions Orgânicos Dependentes de Sódio/biossíntese , Simportadores/biossíntese , Membro 11 da Subfamília B de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Ácidos e Sais Biliares/metabolismo , Colesterol 7-alfa-Hidroxilase/genética , Regulação para Baixo , Humanos , Transportadores de Ânions Orgânicos Dependentes de Sódio/genética , RNA Mensageiro/biossíntese , Simportadores/genética , Regulação para Cima
15.
Neurosci Lett ; 718: 134744, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31923523

RESUMO

Neonatal shaking brain injury (SBI) leads to increases in anxiety-like behavior and altered hormonal responses to psychological stressors as adults. These abnormalities are hypothesized to be due to a change in sensitization in neuronal circuits as a consequence of neonatal SBI. We examined the effects of neonatal SBI on neuronal activity in the anxiety- and/or stress-related areas of adult rats using Fos immunohistochemistry. Exposure to a novel elevated plus maze (EPM) resulted in a marked increase in Fos expression in the parvocellular (PVNp) and magnocellular parts of the paraventricular nucleus and the ventral part of the bed nucleus of the stria terminalis (vBNST) of shaken rats (S group) compared to non-shaken control rats (C group). On the contrary, Fos expression was significantly lower in the medial nucleus of the amygdala and the ventral subiculum (vS) of S group rats than C group rats exposed to EPM. Although we found no significant correlation in the number of Fos-expressing cells in the vBNST and PVNp in the C group rats, these numbers were significantly correlated in the S group rats. Furthermore, in the S group rats, but not in the C group rats, the number of Fos-expressing cells in the vBNST was inversely correlated with that in the vS. Interestingly, previous neuronal tracing studies have demonstrated direct projections from the vS to the vBNST and from the vBNST to the PVNp. The present data suggest that neonatal SBI can alter neuronal activity in anxiety- and/or stress-related neuronal circuits.


Assuntos
Encéfalo/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo , Síndrome do Bebê Sacudido/metabolismo , Estresse Psicológico/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Encéfalo/patologia , Lesões Encefálicas , Teste de Labirinto em Cruz Elevado , Hipocampo/metabolismo , Masculino , Neurônios/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Sprague-Dawley
16.
Acta Histochem Cytochem ; 53(4): 83-91, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32873992

RESUMO

Previous studies have shown that neonatal shaking brain injury (SBI) causes transient microhemorrhages (MHs) in the gray matter of the cerebral cortex and hippocampus. Iron deposits and iron-uptake cells are observed surrounding MHs in this SBI model, suggesting local hypoxic-ischemic conditions. However, whether the shaken pups suffered systemic hypoxic-ischemic conditions has remained uncertain. Further, histopathological correlations of MHs on magnetic resonance imaging (MRI) are still unclear. The present study examined MHs after neonatal SBI using a combination of histochemical and susceptibility-weighted imaging (SWI) analyses. Systemic oxygen saturation analyses indicated no significant difference between shaken and non-shaken pups. MHs on postnatal day 4 (P4) pups showed decreased signal intensity on SWI. Iron histochemistry revealed that these hypointense areas almost completely comprised red blood cells (RBCs). MHs that appeared on P4 gradually disappeared by P7-12 on SWI. These resolved areas contained small numbers of RBCs, numerous iron-positive cells, and punctate regions with iron reaction products. Perivascular iron products were evident after P12. These changes progressed faster in the hippocampus than in cortical areas. These changes in MHs following neonatal SBI may provide new insights into microvascular pathologies and impacts on brain functions as adults.

17.
Neurosci Res ; 160: 57-64, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31790724

RESUMO

To clarify whether photoreception of intrinsically photosensitive retinal ganglion cells (ipRGCs) is related to migraine, we investigated the relationship between hemodynamic responses related to neural activity and visual stimulation of ipRGCs. It has been established that photoreception in ipRGCs is associated with photophobia in migraine. However, the relationship between visual stimulation of ipRGCs and hemodynamic responses in the visual cortex has not been clarified. Hemodynamic responses in the visual cortex were measured using functional near-infrared spectroscopy (fNIRS) as signals reflecting changes in oxygenated and deoxygenated hemoglobin concentrations. Different types of visual stimulation generated by a metamerism method were applied to the peripheral field of the eye of patients with migraine (N = 20) and healthy participants (N = 21). The stimulation intensity on the retina was controlled using an artificial pupil. In the primary visual cortex of patients with migraine, statistically significant changes in fNIRS signals dependent on visual stimulation intensity applied to ipRGCs were observed (p < 0.01), while no such changes were observed in healthy participants. These results reveal that visual stimulation of ipRGCs projecting to the primary visual cortex is involved in hemodynamic responses in patients with migraine, suggesting that ipRGCs, in addition to photometric values related to cones, are associated with migraine.


Assuntos
Transtornos de Enxaqueca , Células Ganglionares da Retina , Hemodinâmica , Humanos , Luz , Estimulação Luminosa , Retina , Opsinas de Bastonetes
18.
Acta Histochem Cytochem ; 53(6): 139-146, 2020 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-33437100

RESUMO

Microglial activation is a component of neurodegenerative pathology. Here, we examine whether activated microglia participate in age-related dopaminergic (DA) cell death in the substantia nigra pars compacta (SNc) of the zitter (zi/zi) rat, a mutant characterized by deletion of the attractin gene. Confocal microscopy with double-immunohistochemical staining revealed activated microglia-formed cell-clusters surrounding DA neurons in the SNc from 2 weeks after birth. An immunoelectron microscopic study showed that the cytoplasm of activated microglia usually contains phagosome-like vacuoles and lamellar inclusions. Expression levels of the pro-inflammatory cytokines interleukin-1ß (IL-1ß), tumor necrosis factor-α (TNF-α) and inducible nitric oxide synthase (iNOS) were increased in the midbrain of 2-month-old zi/zi rats. Chronic treatment with the anti-inflammatory agent minocycline altered the morphology of the microglia, reduced cluster formation by the microglia, and attenuated DA cell death in the SNc, and reduced the expression of IL-1ß in the midbrain. These results indicate that activated microglia, at least in part and especially at the initial phase, contribute to DA cell death in the SNc of the zi/zi rat.

19.
Liver Int ; 29(3): 406-14, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18662272

RESUMO

BACKGROUND/AIMS: The hepatic expression of bile acid transporters is altered in experimental cholestasis and it is unclear whether regulation exists in human cholestatic diseases. We investigated the expression of genes involved in bile acid detoxification, basolateral export and nuclear factor regulation in untreated primary biliary cirrhosis (PBC). METHODS: Liver tissues were obtained from patients with early-stage and late-stage PBC. The hepatic expression levels of messenger RNAs were determined by the real-time reverse transcription polymerase chain reaction. RESULTS: The hepatic expression of multidrug-resistance protein 4 messenger RNA was significantly upregulated in early-stage and late-stage PBC patients compared with controls. The hepatic expression of multidrug-resistance protein 2 and multidrug-resistance protein 3 messenger RNAs was significantly elevated only in early-stage PBC patients. The hepatic expression levels of farnesoid X receptor, fetoprotein transcription factor and constitutive androstane receptor mRNAs were correlated with those of multidrug-resistance protein 2, multidrug-resistance protein 3 and multidrug-resistance protein 4 respectively. CONCLUSIONS: The hepatic expression of multidrug-resistance protein 4 was enhanced in patients with untreated PBC at all stages. However, the hepatic expression of multidrug-resistance protein 2 and multidrug-resistance protein 3 was enhanced only in early-stage patients. The lack of upregulation of these proteins might contribute to the progression of PBC.


Assuntos
Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica/fisiologia , Cirrose Hepática Biliar/metabolismo , Fígado/metabolismo , Glicoproteínas de Membrana/metabolismo , Southwestern Blotting , Receptor Constitutivo de Androstano , Proteínas de Ligação a DNA/metabolismo , Humanos , Microscopia de Fluorescência , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Sondas de Oligonucleotídeos/genética , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/metabolismo
20.
J Med Libr Assoc ; 97(1): 4-11, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19159007

RESUMO

OBJECTIVES: This study was designed to document the state of open access (OA) in the biomedical field in 2005. METHODS: PubMed was used to collect bibliographic data on target articles published in 2005. PubMed, Google Scholar, Google, and OAIster were then used to establish the availability of free full text online for these publications. Articles were analyzed by type of OA, country, type of article, impact factor, publisher, and publishing model to provide insight into the current state of OA. RESULTS: Twenty-seven percent of all the articles were accessible as OA articles. More than 70% of the OA articles were provided through journal websites. Mid-rank commercial publishers often provided OA articles in OA journals, while society publishers tended to provide OA articles in the context of a traditional subscription model. The rate of OA articles available from the websites of individual authors or in institutional repositories was quite low. DISCUSSION/CONCLUSIONS: In 2005, OA in the biomedical field was achieved under an umbrella of existing scholarly communication systems. Typically, OA articles were published as part of subscription journals published by scholarly societies. OA journals published by BioMed Central contributed to a small portion of all OA articles.


Assuntos
Acesso à Informação , Bibliometria , Disseminação de Informação/métodos , Armazenamento e Recuperação da Informação/estatística & dados numéricos , Internet/estatística & dados numéricos , Publicações Periódicas como Assunto/estatística & dados numéricos , Setor Público/estatística & dados numéricos , Pesquisa Biomédica , Humanos , Fator de Impacto de Revistas , Editoração/estatística & dados numéricos
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